Higher HPV16 and HPV18 Penile Viral Loads Are Associated With Decreased Human Papillomavirus Clearance in Uncircumcised Kenyan Men.

BACKGROUND: Whether higher penile human papillomavirus (HPV) viral load is associated with a lower rate of HPV clearance remains unknown. OBJECTIVES: We examined the association between penile HPV16 and HPV18 viral load and subsequent HPV clearance in uncircumcised Kenyan men. STUDY DESIGN: Participants were human immunodeficiency virus (HIV)-seronegative, sexually active, 18- to 24-year-old men randomized to the control arm of a male circumcision trial in Kisumu, Kenya. Men provided exfoliated penile cells from two anatomical sites (glans/coronal sulcus and shaft) every 6 months for 2 years. GP5+/6+ polymerase chain reaction was used to identify 44 HPV-DNA types. Human papillomavirus viral load testing was conducted using a LightCyler real-time polymerase chain reaction assay; viral load was classified as high (>250 copies/scrape) or low (≤250 copies/scrape), for nonquantifiable values. The Kaplan-Meier method and Cox regression modeling were used to examine the association between HPV viral load and HPV clearance. RESULTS: A total of 1097 men, with 291 HPV16 and 131 HPV18 cumulative infections over 24 months were analyzed. Human papillomavirus clearance at 6 months after first HPV detection was lower for high versus low viral load HPV16 infections in the glans (adjusted hazard ratio [aHR], 0.65; 95% confidence interval [CI], 0.46-0.92)] and shaft (aHR, 0.44; 95% CI, 0.16-0.90), and HPV18 infections in the glans (aHR, 0.05; 95% CI, 0.01-0.17). DISCUSSION: High versus low HPV viral load was associated with a reduced HPV clearance for HPV16 infections in the glans and shaft, and for HPV18 infections in the glans, among young uncircumcised men. Reduced clearance of high viral load HPV16 and HPV18 infections in men may increase HPV transmission to their female partners as well as enhance the development of penile lesions in comparison to men with low viral load HPV infections.